Electric lamp



y 1939- c. BIRDSEYE 2,157,051

ELECTRIC LAMP Filed March 25, 1937 Patented May 2, 193a 2,157,051

UNITED STATES PATENT OFFICE- ELECTRIC LAMP Clarence Birdseye, Gloucester, Masa, assignor to Birdseye Electric Company, a corporation of Delaware Application March 25, 1937, Serial No. 133,014

11 Claims. (Cl. 176-32) This invention relates to the manufacture of system of lamp manufacture without requiring incandescent electric lamps and consists in an additional steps or complications. improved construction mechanically uniting the From this standpoint the invention consists glass bulb and the metal base. It is the usual in an improved process of basing lamps which practice to depend upon cement for attaching is characterized by the steps of snapping a cir- 5 the base to the neck of the bulb, but in the cular resilient clip or anchor piece over the sealcase of higher wattage lamps and lamps eming bead in the neck of the bulb and then enploying a. reflecting surface upon or within the closing the encircled neck by a base having bulb a high degree of heat is developed which clip-engaging depressions and containing a is likely to impair the adhesive properties of the charge of cement which may or may not have 10 cement and to result in a looseness which someadhesive properties but which is capable of acttimes permits separation of the bulb from the 8 to Prevent displacement of the p and its base or twisting and short circuiting of the lead mechanical disengagement from the sealing bead wire on the one hand and the metal base on the other.

My invention has for its object the provision Whil i is preferred to have the p n- 15 of a mechanically attached base which will obh r pi a tua y e a th the neck of the viate the difficulties above discussed and which bulb d the anchor P useful results a may be constructed with very little departure achieved when the clip e g the eck and from the present standard practice of basing is embedded in a body of cement which is united incandescent lamps. In one aspect my invento or interlocked with surface irregularities of 20 tion consists in an anchor member which may the base. In fact useful results are achieved be emb dded in the u al mass of c ment a d when the cement itself enters and hardens in maintained in shape thereby and which makes depressions or about irregularities in the neck mechanical engagement with the bulb on the one d e- 5 hand, and the met l base on th other. I h v A further feature of the invention consists in found that under conditions of excessive heat means for preventing relative twisting o e the cement may completely lose its adhesive ec a base even When the adhesive p p properties without physical disintegration so ties of the cement are destroyed by overheating. that it is still capable of serving as a filler or This may be effected, as herein shown, by propositioning medium and of withstanding appreviding some part of the bulb neck and the base 30 ciable compressive strength. This property of with depressions or other irregularities which the cement makes it possible to employ an anengage or interlock with the clip and so prechor member of light sheet metal which may vent or limit circumferential movement of one be easily manufactured, shaped and fitted to part with respect to another.

the p Parts and that Once S0 fitted is rigidly These and other features of the invention will 35 maintained in efl'ective position by the cement b b t understood and appreciated from the surrounding it. following description of a preferred embodiment he anchor Pieces herein Shown for illustrathereof, together with several alternative forms tive purposes may be s mpe or i d Out fr m of clip or anchor piece selected for purposes of 40 thin sheet metal and then shaped and otherillustration and Shown in t accompanying 40 wise treated to present a resilient conical shape drawing, in which, having at its base edge, surfaces which may Fig 1 is a View in perspective Showing the be f over the sealmg bead the bulb end of a. bulb neck with a clip or anchor piece and at its upper edge members or sections shaped in position thereon g; 23 i sgifig fi g gf fiig formed Fig. 2 is a view in elevation, partly in section, 45

While I may take advantage of any surface i g gfi g assembled relatlon upon irregularity in the neck of the bulb to make inhe o e terlocking engagement with the anchor piece, I .3 F View on an enlarged prefer to utilize the ledge or shoulder presented scale showmg particularly connection 50 by the bead of the fiarewhere it is sealed to the base and the neck of the bulb, neck. Since this sealing head is found in prac- 4 1S a P View 9 the blank from which tically all electric lamps made under commercial the Clip anchor Piece is made. v conditions of manufacture the present invention Fig. 5 is a view in perspective of the completed has the advantage of fitting into the established clip, 55

Figs. 6 and 7 are similar views of clips of alternative construction.

The lamp partially shown in Figs. 1-3 comprises a bulb of usual commercial construction terminating in a neck III of reduced diameter. Within the neck is disposed the usual mount I4 having a flare I8 which is sealed. to the end of the neck, presenting a circular bead I2 which projects slightly beyond the tapered end surface of the neck. The bead I2 may be more or less irregular in its shape and frequently does not extend symmetrically about the. entire circumference of the neck, but the exact shape of the bead is of secondary importance only in the present instance. It need only present a surface irregularity of sufficient extent to be engaged at one or two points by the clip or anchor piece in order to serve satisfactorily as a part of the connection contemplated by my invention.

The anchor piece or clip may be formed of thin sheet metal having suflicient resiliency to be sprung over the bead I2. This member is shown in its preferred form in Figs. 4 and 5. It may be stamped or died from sheet metal as a perforated circular blank, shown in Fig. 4 as having short outwardly extending prongs or projections 2I and longer inwardly extending prongs or projections 22. These are shown as'symmetrically arranged in radial relation, the prongs 22 defining at their inner ends a circle which is somewhat smaller in diameter than the diameter of the bead I2 with which the clip is to be used. After the clip has been first produced as a flat blank it is given a conical shape shown in Fig. 5 and may at this time or previously be treated so that it is made inherently resilient. In the first step of the process the clip shown in Fig. 5 is merely snapped over the bead I2 of the bulb, the inwardly extending prongs 22 yielding for this purpose and then engaging the ledge or shoulder presented by the bead. On account of its shape and resilient character the clip hugs the tapering end surface of the neck and the prongs 22 make positive engagement with the bead so that the clip cannot be removed except by bending the individual prongs outwardly.

The metal base I6 may be of commercial construction in its general shape and appearance, but is preferably provided near its open end with a series of circular corrugations I8. Any other shape of depression or surface irregularity'would serve which might be adapted for interlocking engagement with the prongs 2| of the clip. As shown in Figs. 2 and 3 the base I6 is provided also with an annular cement retaining shoulder I1 and with the usual thread for screwing into a socket or other fixture.

In the present commercial system of basing lamp bulbs a charge of thermoplastic cement is supplied to the base and then the base is applied to the end of the neck and held in position while the cement is heated until a union is formed with the glass of the neck. In accordance with the process of my invention no departure is required from this commercial procedure. The base I6 is provided with a charge of plastic cement I9 which is retained in position in thebase by an annular shoulder II. The base is then pressed onto the end of the neck I0 and in this movement the corrugations I8 are advanced beyond the ends of the outwardly extending prongs 2| of the clip. The latter are first contracted by the relatively stiff cement in the base and then, when the cement is softened by heat, they spring out resiliently from the surface of the neck and snap into one or another of the corrugations I8 and become mechanically interlocked therewith so that it is impossible to retract or remove the base. In this operation the .plastic cement I8 is caused to flow about the clip so that the prongs thereof become embedded in cement as best shown in Fig. 3. The cement hardens within a short time and acts-effectively to prevent displacement of the clip and particularly to prevent disengagement of the interlocking engagement between the inwardly extending prongs 22 and the shoulder of the flange I2 on the one hand and the outwardly extending prongs 2I and the. corrugations of the base on the other hand. The result is that the clip is permanently positioned in interlocking engagement and-she relationship of the parts cannot be disturbed so long as the cement acts as a filler or positioning medium for the clip.- If the cement isheated to the point that it loses its adhesive properties it is still effective indefinitely as a flller and positioning medium and the mechanical connection of the metal base and glass neck is permanently maintained.

The construction thus far described effectively prevents disengagement of the bulb and base in a lengthwise direction but it may not prevent an objectionable twisting of one part with respect to another. In order to guard against such a contingency the neck of the bulb, as shown in Fig. 3, may be provided with spaced depressions or grooves 28 and the base may be perforated in the area of the corrugations I8 for interlocking engagement with the prongs 22 and 2I respectively. In the illustrated embodiment of this feature the depressions 20 taper outwardly from the flange I2 of the bulb and each is adapted to receive a substantial portion of 2. prong 22 either when the base is applied thereto or to receive one of the prongs when and if relative twisting of the parts occurs. The perforations in the base may be merely such as to receive the end of one of the prongs 2I and are preferably located in the bottom of the corrugations I8 which thus act to guide the prongs into the perforations. It will be apparent that when such interlocking engagement has taken place twisting movement between the parts is positively prevented.

The shape of the clip may be varied within a wide range so long as it presents a resilient edge or resilient prongs adapted to be sprung over the bead of the bulb. It is preferred to employ a clip which may be stamped out conveniently as a fiat blank from sheet material and then given its final form by a die-pressing operation. One such form of clip or anchor piece has already been described. An alternative form is shown in Fig. 6 in which the clip originally stamped out in the form of a continuous ribbon presenting a series of V-shaped portions circularly arranged. These are subsequently given a conical shape and so present the inwardly extending prongs 24 for engagement with the bead of the bulb and the outwardly extending prongs 25 for engagement with the corrugations of the .base.

In Fig. '7 is shown a clip or anchor member which is stamped out in the form of a slitted ring and then given a conical shape so that it presents a series of inwardly extending prongs 21 for engagement with the bead of the neck and an outwardly extending continuous edge for engagement with the corrugations of the metallic base. While the clips herein shown are made from an integral and endless blank, it will be apparent that the clip may present a gap in its periphery or that its ends may be overlapped if desired.

engaging prongs embedded in cement within the Having now disclosed my invention and described preferred embodiments thereof for illustration and not by way of limitation, I claim as new and desire to secure by Letters Patent.

1. An electric lamp having a bulb provided with surface irregularities in. its neck, a metal base having irregularities on its inner surface and cemented to the neck of the bulb, and a clip embedded in the cement within the base and maintained thereby in engagement with both the neck and the base. i

2. An electric lamp having a bulb provided with surface irregularities in its neck, a metal base having a cement retaining ledge and containing cement, and an inherently resilient clip embedded in the cement within the base and maintained thereby in engagement with both the neck and the base.

3. An electric lamp comprising a bulb having a sealing bead at the end of its neck, a resilient anchor piece held against said bead and having outwardly extending projections, and a metal base cemented to the neck of the bulb and interlocked with the projections of the anchor piece.

.4. An electric lamp comprising a bulb having a shoulder at the end of its neck, a flexible anchor piece engaged with said shoulder and having outwardly extending projections, a metal base interlocked with the projections of the anchor piece, and cement surrounding the anchor piece and contacting with the surface of the neck.

5. An electric lamp comprising a bulb having a sealing bead at the end of its neck, an anchor piece having a series of circularly arranged portions engaging said bead and a series of outwardly extending portions, and a metal base containing cement and having means for engaging with said outwardly extending portions.

6. An electric lamp comprising a bulb having a projecting circular bead in its neck, a base enclosing the end of the neck and having spaced circular corrugations therein, and a resilient clip having bead-engaging prongs and corrugationprojecting circular bead in its neck, a metal base enclosing the end of the neck and having spaced depressions therein, and a metal clip yieldingly contracted upon the neck above the bead and having engaging means which hug the neck and abut against the bead and engaging means which are interlocked with the depressions of the base.

8. An electric lamp comprising a bulb having a neck with tapering walls terminating in a projecting bead, a conical clip engaging the bead, and having outwardly deflected portions, and a metallic base enclosing the end of the neck and containing a charge of cement so located as to embed portions of said clip.

9. An electric lamp comprising a bulb having a neck with tapering walls terminating in a projecting bead, a conical clip having portions fitting the tapering walls of the neck and interlocked with said bead and other outwardly deflected portions, and a metallic base enclosing the end of the neck and containing a charge of cement located to surround said clip and prevent it from spreadmg.

10. An electric lamp comprising a bulb having a neck with tapering walls terminating in a projecting bead, a resilient clip engaging said walls and having a circular opening of less diameter than said bead and portions flaring away from said tapering walls, and a metallic base engaged thereby.

11. An electric lamp including in its structure a bulb, a corrugated metal base, lead wires sealed within the bulb and passing out of its neck portion, and an anchor member having a body engaged with the end of the neck and outwardly projecting resilient prongs engaged with the corrugations in said base.

CLARENCE BIRDSEYE. 

